Narrative:Nearly one hour following takeoff from Arica (ARI) a no. 2 engine power loss occurred. The aircraft was flying over the Andes at that moment, on it's way to Puerto Suarez (PSZ). Te C-46 was overloaded by 1000lbs and could not maintain altitude. The crew were forced to carry out a forced landing on a comparatively open, uphill area when the plane slid through several 3-4 feet high rock retaining walls. The initial cause of the engine malfunction could not be established, however as a result of it the exhaust valve of the no.10 cylinder had failed from its piston beating against the spark plugs and cylinder head. This probably ruptured the intake port, and reduced manifold pressure to atmospheric pressure (22" in flight).

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Map

This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path. Distance from Arica-Chacalluta Airport to Puerto Suarez Airport as the crow flies is 1315 km (822 miles).

This information is not presented as the Flight Safety Foundation or the Aviation Safety Networkĺs opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.